Bluff, Ardour & Assoc.
Toni Visconti didn't master the album, that was done by someone called Emily Lazar. The studio mix and the mastering process are two different things. At this remove, and without anyone being able to hear the final studio mix that Visconti delivered, it's impossible to tell exactly where the fault lays - but ramping up the volume and crushing everything with compression is usually something that occurs at the mastering stage. The vinyl may well be a different master. It's a while since I've listened to it on LP - I'll have to dig it up and give it a whirl.
Indeed. This is actually the source of a great many threads at the informative Steve Hoffman Forums (www.stevehoffman.tv), generally complaining that -x- mastering engineer has ruined -album y- by -z-. I'm not as "aurally sensitive" to so-called "brickwalling" other than noticing that the base volume of mastered recordings seems to get louder and louder as the years go on.
I had a conversation with another fan years ago to the effect that they thought ROTT was mastered for vinyl, but I never got a copy. That would be doubly interesting if there actually variances in the mixes - it could certainly change the overall presentation of the songs. I'd be curious to hear about your findings after you listen.
Also on the topic of the mix, I knew someone who was in close contact with Alain in the Red Lightning/ROTT era and he was apparently "gutted" at the final mix of the album. Given that his guitar playing is nigh-on inaudible or indistinguishable on most songs, I could see why, especially as he wrote the lion's share and contributed the emotional centerpieces ("Dear God Please Help Me," "Life Is A Pigsty").